Cross bar switching apparatus having mechanical locking means



w. J. REA 3,369,203

CROSS BAR SWITCHING APPARATUS HAVING MECHANICAL LOCKING MEANS Feb. 13, 1968 3 Sheets-Sheet 1 Filed Sept. 19, 1966 Hllllll \NVENTOQ WJREA ATTORNEY Wv J. REA

Feb. 13, 1968 CROSS BAR SWITCHING APPARATUS HAVING MECHANICAL LOCKING MEANS 3 heets-Sheet 2 Filed Sept. 19, 1966 E 9 .l l b M 4 Q2, m w a 4 z H lq ill 7 5 l IIIIIJ 'l'l' l a 4 N w 9 a a Y l :11 a Qm W7 2% W} U n 4 a a b :5 a/\. a 24 In H T a a M- Lh l w. 8 Q Z M E m u l a v 4 -nuuu T I I6 I a i F/q "In!" 4 3 a m Mw a 3 i w a 4 4 W. J. REA

Feb. 13, 1968 CROSS BAR SWITCHING APPARATUS HAVING MECHANICAL LOCKING MEANS 3 heets-Sheet 3 Filed Sept. 19, 1966 United States Patent l 3,369,203 CROSS BAR SWITCHING APPARATUS HAVING MECHANICAL LOCKING MEANS William J. Rea, Ralston, Nebr., assignor to Western Electric Company, Incorporated, New York, N.Y., a corporation of New York Filed Sept. 19, 1966, Ser. No. 580,362 '10 Claims. (Cl. 335-112) This invention relates to switching apparatus, and more particularly to crossbar type switching apparatus in which an operated set of contacts is maintained operated mechanically so that an operating mechanism for the set of contacts can be utilized to operate another set of contacts.

At the present time one of the crossbar type switches most commonly used in telephone switching systems includes ten horizontal and ten vertical intersecting rows of crosspoints, with each crosspoint being made up of a plurality of contact springs. The design of this present switch is such that contacts on corresponding movable operating contact springs in each vertical row of crosspoints make with associated contacts on respective ones of a plurality of vertical fixed multiple contact springs. Further, each two adjacent ones of the horizontal rows of crosspoints has an operating mechanism associated therewith which is used to close each of the crosspoints in these rows, and each of the vertical rows of crosspoints has an operating mechanism associated therewith which is used to close each of the crosspoints in the vertical row, and which must be maintained operative after being used to close a crosspoint until that crosspoint is to be opened, namely, on termination of the talking path through the crosspoint. Accordingly, in the operation of this switch only one crosspoint in a vertical row of crosspoints can be closed at any one time, and while the switch has 100 crosspoints the maximum number of connections which can be made through the switch at any one time is ten, one for each of the vertical rows of crosspoints.

In the past, various arrangements have been proposed for increasing the capacity of this type of switch by providing a mechanism for locking an operated crosspoint in operated condition until it is to be released. For example, in one arrangement the operation of the crosspoint energizes an electromagnet which holds the crosspoint operated until the talking path through the crosspoint is terminated. Other proposed arrangements have utilized latch mechanisms of various designs for this purpose.

The above-described arrangements have various disadvantages. For example, in the arrangement using an electromagnet, the electromagnet continuously draws power when it is maintaining the crosspoint operated. Further, the electromagnet thus is subject to becoming de-energized as a result of a momentary interruption in its power circuit, whereby it may inadvertently release the crosspoint prematurely. In the arrangements'utilizing latch mechanisms, the latch mechanisms generally are relatively complex in nature, and in certain instances still achieve only partial utilization of the full crosspoint capacity of the switch at any one time. In other instances the latch mechanisms require additional electromagnets and associated structure for their operation.

Accordingly, an object of this invention is to provide new and improved crossbar type switching apparatus.

A further object of this invention is to provide new and improved crossbar type switching apparatus in which an operated set of contacts is maintained operated mechanically so that an operating mechanism for the set of contacts can be utilized for operating another set of contacts.

A still further object of this invention is to provide new and improved crossbar type switching apparatus in which no electrical power is required-to maintain a set of contacts operated.

3,3692% Patented Feb. 13,, 1968 Another object of this invention is to provide new and improved crossbar type switching apparatus in which crosspoints of the switch all can be operated at any one time.

A further object of this invention is to provide new and improved crossbar type switching apparatus in which a mechanism for maintaining a set of contacts operated involves a relatively small amount of structure of a relatively simple nature as compared to prior known apparatus.

In accordance with the invention, a contact selecting means is movable selectively into either of two operative conditions, each associated with a respective one of first and second adjacent sets of contacts. A releasable means cooperates with the contact selecting means when it is in either of its two operative conditions for operating the set of contacts which is associated with that condition, and mechanical locking means, mounted at least in part on said contact selecting means for movement therewith, is provided for lockingthe operated set of contacts in operated condition so that the contact selecting means and the releasable means can be utilized to operate the other set of contacts.

In a preferred embodiment of the invention, cross-bar type switching apparatus includes first and second adjacent pairs of contact springs which are insulated from one another, with one contact spring of each pair being an input terminal and the other contact spring of each pair being an output terminal. An operating card of insulating material is engaged with each pair of contact springs, and a movably mounted selecting bar has a selecting finger and a pair of resilient locking fingers mounted thereon. The selecting bar is selectively movable from a neutral position into either of two operative positions to position the selecting finger adjacent one of the operating cards and to position a respective one of the resilient locking fingers in engagement with a tang portion of the operating card. An operating member then is moved so as to move the selecting finger and the operating card, whereby the operating card moves its respective pair of contact springs into electrical contact with an interconnecting terminal member to close a circuit through the contact springs. At the same time the tang portion on the operating card moves into spaced relationship with respect to a fixed member so that the resilient locking finger moves into the space between the tang portion and the fixed member. The operating member and the operating card then are moved in a reverse direction to release the selecting finger, and to trap the resilient locking finger between the tang portion and the fixed member so that the pair of contact springs is maintained operated. The selecting finger and the operating member then can be utilized to operate the other pair of contact springs.

This invention, together with further objects and advantages thereof, will best be understood by reference to the following detailed description taken in connection with the accompanying drawings, in which:

FIG. 1 is a front elevational view of switching apparatus in accordance with the invention, partially broken away;

FIG. 2 is an enlarged cross-sectional view of the apparatus taken substantially along the line 22 of FIG. 1;

FIG. 3 is a further enlarged, partial cross-sectional view of the apparatus taken substantially along the line 3-3 of FIG. 1;

FIG. 4 is a partial cross-sectional view of the apparatus taken substantially along the line 4-4 of FIG. 3;

FIG. 5 is a further enlarged, partial cross-sectional view of the apparatus taken substantially along the line 55 of FIG. 2 and illustrating a pair of adjacent crosspoints of the apparatus in an inoperative (open) condition.

FIG. 6 is a cross-sectional view similar to FIG. 5 illustrating an operating phase of the apparatus during the closing of one of the crosspoints;

FIG. 7 is a cross-sectional view similar to FIG. 6 illustrating a subsequent operating phase of the apparatus during the closing of the one crosspoint;

FIG. 8 is a cross-sectional view similar to FIG. 7 illustrating the apparatus after the one crosspoint has been closed and locked operated;

FIG. 9 is a cross-sectional view similar to FIG. 8 illustrating a subsequent operating phase of the apparatus during the closing of the second crosspoint; and

FIG. 10 is a cross-sectional view similar to FIG. 9 illustrating the apparatus after both of the crosspoints have been closed and locked operated.

Referring to FIG. 1 of the drawings, it is seen that the illustrated embodiment of the invention involves a crossbar type switching apparatus which includes ten vertical unit assemblies 12 (only six being shown), each having ten crosspoints 13, thereby forming ten horizontal and ten vertical intersecting rows of the crosspoints. The crosspoints 13, which are insulated from one another, all can be closed at one time as subsequently will become apparent, whereby the full crosspoint capacity of the switching apparatus can be utilized at any one time.

Each of the vertical unit assemblies 12 includes a vertically extending mounting plate 14 which is secured adjacent its upper and lower ends by suitable screws 16 to a frame 17 of the switching apparatus. As is best shown in FIGS. 2 and 3, each of the vertical unit assemblies 12 also includes a contact spring sub-assembly 18 in the form of a mounting block 19 having ten vertically spaced sets of operating contact springs 21 molded therein, each of the sets of contact springs forming a part of one of the crosspoints 13. The contact spring sub-assembly 18 may be formed in any suitable manner, and in the illustrated embodiment of the invention the mounting block 19 of the sub-assembly includes a rectangular box-shaped frame 22 in which the operating contact springs 21 are suitably positioned while an electrical insulating molding material 23 (FIG. 3) is cast in the box-shaped frame to form the rigid sub-assembly. The operating contact springs 21 project rearwardly of the mounting block 19 (FIG. 2) for wiring purposes and also project forwardly of the mounting block. The mounting block 19 is secured to the vertical mounting plate 14 of the vertical unit assembly 12 by suitable screws.

The forward portion of each of the operating contact springs 21 is bifurcated and, as is shown in FIG. 4, the furcations are provided with precious metal contacts 24 in a well known manner. The operating contact springs 21 of each of the crosspoints 13 are arranged in pairs, with one contact spring of each pair being an input terminal and the other contact spring of the pair being an output terminal. The closing of circuits through these pairs of operating contact springs 21 to establish a connection through the crosspoint 13 is accomplished by movement of the contact springs in unison to the left, as viewed in FIG. 4, so that the precious metal contacts 24 of each pair come into electrical contact with respective contact legs of an associated U-shaped, interconnecting terminal member 26 of a suitable electrically conducting material. While three pairs of the operating contact springs 21 are shown in FIGS. 3 and 4, this being the minimum normally required for telephone switching purposes, the number of pairs of the contact springs may be varied as desired.

The U-shaped interconnecting terminals 26 for the operating contact springs 21 of each crosspoint 13 are mounted in an associated block member 27 of molded insulating material, such as plastic, and as is best shown in FIGS. 1 and 2, each of the vertical unit assemblies 12 includes a plurality of the block members arranged in vertically spaced relationship. More specifically, as is shown in detail in FIG. 4, the interconnecting terminals 26 for the operating contact springs '21 of one of the crosspoints 13 which is above and immediately adjacent a vertically intermediate one of the block members 27, are mounted in the block member so that their contact legs extend upward from the block member into opposed, normally spaced relationship with respect to the precious metal contacts 24 on the contact springs, while the interconnecting terminals 26 for the contact springs 21 of the crosspoint 13 which is below and immediately adjacent the intermediate block member are mounted in the block member so that their contact legs extend downward from the block member into opposed, normally spaced relationship with respect to the precious metal contacts 24 on these contact springs. Similarly, referring to FIG. 2, it is seen that the interconnecting terminals 26 for the operating contact springs 21 for the uppermost crosspoint 13 in each of the vertical unit assemblies 12 are mounted in the uppermost block member 27 of the assembly so that their contact legs extend downward adjacent the precious metal contacts 24 (not shown in FIG. 2) on the contact springs, while the interconnecting terminals 26 for the contact springs 21 of the lowermost crosspoint 13 in the vertical unit assembly are mounted in the lowermost block member 27 of the assembly so that their contact legs extend upward adjacent the precious metal contacts 24 on these contact springs.

Adjacent the left-hand sides of the block members 27 in each of the vertical unit assemblies 12, as viewed in FIG. 1, is a vertically extending side plate member 28. The side plate member 28 and the block members 27 are secured together and to the vertical mounting plate 14 of the vertical unit assembly 12 by suitable screws extending through the side plate member and the block members and screw threaded into forwardly projecting lugs 14a (FIGS. 3 and 4) on the mounting plate.

The movement of the pairs of operating contact springs 21 for each of the crosspoints 13 to the left, as viewed in FIGS. 3 and 4, to bring their precious metal contacts 24 into electrical contact with the contact legs of their respective interconnecting terminals 26, is accomplished by mechanism including an operating card 29 of a suitable insulating material, such as plastic. The operating card 29 is mounted between the furcations of the operating contact springs 21 and has a series of slots formed in its upper and lower sides in which the furcations of the contact springs are received in a manner well known to those skilled in the art. Adjacent the left-hand side of the operating card 29, as viewed in FIGS. 3 and 4, it extends through an aperture 28a in the side plate member 28 of the vertical unit assembly 12 in which it is located, and adjacent its right-hand side, as viewed in these figures, it extends through an aperture in a vertical armature member 31 of the vertical unit assembly.

The operating contact springs 21 bias the operating card 29 to the right, as viewed in FIGS. 3 and 4, into a position in which the precious metal contacts 24 on the contact springs are in their normally spaced relationship relative to the contact legs of their interconnecting terminals 26 and in which a vertically extending tang portion 29a of the operating card is engaged against the vertical side plate member 28. As will subsequently be described in detail, the operating card 29 is movable to the left in FIGS. 3 and 4 by the vertical armature 31 and an associated crosspoint selecting finger 32, to move the pairs of operating contact springs 21 so that the precious metal contacts 24 thereon come into electrical contact with the contact legs of their interconnecting terminals 26, thereby closing the crosspoint 13, and so that the tang portion 29a on the operating card moves into spaced relationship with respect to the side plate member 28 for subsequent locking of the crosspoint operated.

The vertical armature 31 of each of the vertical unit assemblies 12 is utilized for closing all of the crosspoints 13 in that assembly, and is pivoted adjacent its upper and lower ends on the mounting plate 14 of the assembly in a suitable manner for movement about a vertical axis. The

vertical armature is biased to a normally inoperative position by an elongated leaf-type restoring or balancing spring 33 (FIG. 2) secured adjacent one end on the mounting plate 14 and having its other end engaged with the vertical armature. The vertical armature 31 is pivotable into a crosspoint closing position against the action of the balancing spring 33 by an electromagnet 34 suitably secured on the mounting plate 14.

Each of the selecting fingers 32 is utilized for closing two adjacent ones of the crosspoints 13. In this regard, referring to FIGS. 1 and 3, it is seen that the crosspoint selecting fingers 32 are mounted on a plurality'of horizontally extending selecting bars 36, one of the selecting bars being provided for each pair of horizontal rows of the crosspoints 13 and each of the selecting bars having one selecting finger thereon for each of the vertical unit assemblies 12. As is shown in FIG. 1, each selecting bar 36 is journalled adjacent its opposite ends on the frame 17 of the switching apparatus for movement about a horizontal axis and is biased to a neutral position by suitable leaf-type centering springs 37 mounted on the frame by means of a suitable bracket 37 and engaged with a laterally projecting stud 36a on a rearwardly extending end lug of the selecting bar in a well known manner. Each selecting bar 36 also is rotatable from its neutral position selectively in either direction through an arc of approximately into an upper or a lower crosspoint closing position by the energization of one or the other of two associated upper and lower electromagnets 38 and 39 suitably mounted on the frame 17.

As is best shown in FIG. 3, each of the selecting fingers 32 is of a conventional type, including a coil spring portion and an elongated resilient portion integral therewith. In the illustrated embodiment of the invention the coil spring portion of each of the selecting fingers 32 is suitably secured on a stud member 41, such as by being screwed onto a threaded portion thereof, and the stud member is screw threaded into the respective selecting bar 36.

In accordance with the invention, a mechanical locking mechanism is provided for maintaining each of the crosspoints 13 in a closed condition after it has been operated, without the use of any electrical power, and so that its associated vertical armature 31 and selecting bar 36, which are actuated sequentially for the purpose of closing the crosspoint, then can be used either sequentially in combination, or in combination with other ones of their associated selecting bars and vertical armatures, respectively, for closing other ones of their associated crosspoints. In this connection, referring to FIGS. 2 and 3, it is seen that the selecting bars 36 have pairs of upper and lower resilient locking fingers 42 and 43 mounted thereon adjacent the tang portions 29a of the operating cards 29, with one of the locking fingers being provided for each of the crosspoints 13. The upper locking fingers 42 on each of the selecting bars 36 are arranged for locking respective ones of the crosspoints 13 in the horizontal row of crosspoints above the selecting bar in operated condition, while the lower locking fingers 43 on the selecting bar are arranged for locking respective ones or the crosspoints in thehorizontal row of crosspoints below the selecting bar in operated condition.

More specifically, each of the crosspoint locking fingers 42 or 43 includes an elongated portion which is arranged to be trapped between the tang portion 29a of the operating card 29 of its respective crosspoint 13, and the side plate member 28 of the vertical unit assembly 12 in which the crosspoint is located, as is illustrated in FIGS. 8 and 10, to lock the crosspoint operated, in a manner subsequently described in detail in the operation of the apparatus. In this regard, each of the pairs of crosspoint locking fingers 42 and 43 is spaced from its respective selecting finger 32 a distance determined by the distance between the tang portion 29a of the operating card and an operating face 29b thereof. As in the case of the selecting fingers 32, each of the crosspoint locking fingers 42 or 43 is mounted on its associated selecting bar 36 for movement therewith by means of a screw threaded stud 44 (FIGS. 2 and 3) to which a coil spring portion of the finger is suitably secured. Between each of the pairs of crosspoint locking fingers 42 and 43 is a projecting stop member 46 which is fixed on the adjacent side plate member 28 and which limits the movement of each of the locking fingers when the other locking finger moves into a crosspoint locking position as a result of rotation of the selecting bar 36 on which the locking fingers are mounted.

Operation With the switching apparatus in inoperative condition as shown in FIGS. 1 through 4, the closing of one of the crosspoints 13, as for example one of the crosspoints in the lower of the two horizontal rows of crosspoints associated with one of the selecting bars 36, is accomplished by energizing the selecting bars upper electromagnet 38 (FIG. 1) to rotate the selecting bar from its neutral position counterclockwise, as viewed in FIG. 2, into its lower crosspoint closing position. This rotation of the selecting bar 36 causes movement of each of the selecting fingers 32 thereon from a neutral position, as shown in FIG. 5, into a position between its associated vertical armature 31 and the operating face 2% of the operating card 29 of its associated lowermost crosspoint, as shown in FIG.

. 6. This rotation of the selecting bar 36 also causes movement of each of the lower crosspoint locking fingers 43 thereon from a position, as shown in FIG. 5, into a position in which the locking finger is engaged with the tang portion 29a of its respective operating card, as shown in FIG. 6. During this rotation of the selecting bar 36, movement of the upper crosspoint locking fingers 42 thereon is limited by their respective stop members 46 on the side plate members 28.

The vertical armature 31 of the vertical unit assembly 12 (FIGS. 1, 2 and 3) containing the crosspoint 13 (FIG. 6) which is to be operated then is pivoted by energization of its operating electromagnet 34 (FIGS. 1 and 2) so that it moves the selecting finger 32, and thus the operating card 29 of the crosspoint, to the left into the position shown in FIG. 7. As is apparent from FIG. 7, this movement of the operating card 29 causes it to move the pairs of operating contact springs 21 with which it is engaged so that the precious metal contacts 24 on the contact springs make electrical contact with the contact legs of their respective interconnecting terminals 26, thereby closing the crosspoint 13. Further, as a result of this movement of the operating card 29 its tang portion 29a moves into spaced relationship with respect to the adjacent side plate member 28, whereby the resilient crosspoint locking finger 43 which is engaged with the tang portion slides OR of the tang portion and springs into the space between the tang portion and the side plate member.

The operating electromagnet 34' (FIGS. 1 and 2) for the vertical armature 31 then is deenergized and the vertical armatures balancing spring 33 (FIG. 2) returns it to its inoperative position. When the vertical armature 31 is released the operating contact springs 21 of the closed crosspoint 13 move the crosspoints operating card 29 to the right, as viewed in FIGS. 7 and 8, toward its inoperative position until the tang portion 29a of the operating card traps the resilient crosspoint locking finger 43 between the tang portion and the side plate member 28. In this regard, the distance moved by the operating card 29 is such that the precious metal contacts 24 on the operating contact springs 21 do not break electrical contact with the contact legs of their interconnecting terminals 26, and thus the locking finger 43 and the tang portion 29a of the operating card cooperate to lock the crosspoint 1-3 in operated condition, as shown in FIG. 8.

The upper electromagnet 38 (FIG. 1) for the selecting bar 36 then also is deenergized, whereby the selecting bar and the selecting fingers 32 thereon are restored to their neutral positions by the selecting bars centering springs 37 (FIG. 1). The resilient crosspoint locking finger 43, however, remains trapped between the tang portion 29a of the operating card 29 and the side plate member 28 by friction, as shown in FIG. 8, so that the crosspoint 13 remains operated. The vertical armature 31 now can be used to close any of the other crosspoints 13 in its associated vertical unit assembly 12, and the selecting bar 36 and the selecting fingers 32 thereon can be used to close any of the other crosspoints 13 in their associated two horizontal rows of the crosspoints, as desired.

For example, to close the upper crosspoint 13 in FIGS. 5 through 10, the lower electromagnet 39 (FIG. 1) for the selecting bar 36 is energized to rotate the selecting bar clockwise, as viewed in FIG. 2, into its upper crosspoint closing position. This rotation of the selecting bar 36 now causes movement of the selecting finger 32 used for closing the lower crosspoint 13, as above described, into a position between the vertical armature 31 and the operating face 29b of the operating card 29 of the upper crosspoint, and also causes movement of the upper resilient crosspoint locking finger 42 into engagement with the tang portion 2% of this operating card 29 adjacent the side plate member 28. During this rotation of the selecting bar 36, the lower resilient crosspoint locking finger 43 remains trapped by friction between the tang portion 29a of the operating card 29 of the lower crosspoint 13 and the side plate member 28, as shown in FIG. 8.

The vertical armature 31 now is pivoted by its operating electromagnet 34 (FIGS. 1 and 2) to move the selecting finger 32 and the operating card 29 of the upper crosspoint 13 to operative condition, so that the operating card moves the pairs of operating contact springs 21 with which it is engaged to the left, as viewed in FIG. 9, whereby the precious metal contacts 24 on the contact springs make electrical contact with their respective interconnecting terminals 26 to close the crosspoint. This movement of the operating card 29 also causes the tang portion 29a thereof to move into spaced relationship with respect to the side plate member 28 and the upper resilient crosspoint locking finger 42 slides off of the tang portion and springs into the thus created space between the tang portion and the side plate member, as is shown in FIG. 9.

The operating electromagnet 34 (FIGS. 1 and 2) for the vertical armature 31 then is deenergized to release the vertical armature to its inoperative position. As in the case of the lower crosspoint 13, the operating contact springs 21 of the upper crosspoint 13 then move the operating card 29 of the crosspoint back toward its inoperative position so as to trap the upper resilient crosspoint locking finger 42 between the tang portion 29a of the operating card and the side plate member 28 without the precious metal contacts 24 on the contact springs breaking electrical contact with their interconnecting terminals 26. Then, upon deenergization of the lower electromagnet 39 (FIG. 1) for the selecting bar 36, the selecting bar and the selecting finger 32 are returned to their neutral positions by the action of the selecting bars centering springs 37 (FIG. 1). The upper resilient cl'Osspoint locking finger 42, however, remains trapped between the tang portion 29a of the operating card 29 of the upper crosspoint 13 and the side plate member 28, as illustrated in FIG. 10, whereby both the upper and lower crosspoints now are locked operated. The vertical armature 31 now is available for closing the other cross points 13 in its associate-d vertical unit assembly 12, and the selecting bar 36 is available for closing the other crosspoints in its two associated horizontal rows of crosspoints.

In the releasing of an operated one of the crosspoints 13, as for example the lower crosspoint shown in FIGS. 5 through 10, the selecting bar 36 is rotated by its upper electromagnet 38 (FIG. 1) to position the selecting finger 32 between the operating face 2% of the operating card 29 of the crosspoint and the vertical armature 31. The vertical armature 31 then is pivoted by energization of its operating electromagnet 34 (FIGS. 1 and 2) to move the selecting finger 32 and the operating card 29 to the left, as viewed in FIGS. 5 through 10, thereby moving the tang portion 29a of the operating card into spaced relationship with respect to the side plate member 28 a distance such that the lower resilient crosspoint locking finger 43 is no longer frictionally trapped between the tang portion and the side plate member. Next, the upper electromagnet 38 for the selecting bar 36 is deenergized so that it is restored to its neutral position by its centering springs 37 (FIG. 1), and the crosspoint locking finger 43 now returns to its inoperative position with the selecting bar. The electromagnet 34 then is deenergized to release the vertical armature 31 to its inoperative position, whereupon the contacts 24 on the operating contact springs 21 of the crosspoint 13 break contact with their interconnecting terminals 26 and return the operating card 29 to its inoperative position. At substantially the same time the resilient selecting finger 32, which is in a flexed state as a result of the selecting bar 36 already having been returned to its neutral position, becomes released from between the operating card 29 and the vertical armature 31 and returns to its neutral position. The upper crosspoint 13 shown in FIGS. 5 through 10 is released in a similar manner, utilizing the lower electromagnet 39 for the selecting bar 36, whereupon the apparatus will have been restored to its initial inoperative condition, as shown in FIG. 5.

- While the foregoing description of the apparatus is directed to the closing and releasing of each crosspoint individually, it is apparent that after one of the selecting bars 36 has been rotated into either its upper or lower crosspoint closing position, any selected ones of the crosspoints 13 in the associated horizontal row of crosspoints can be closed in sequence or simultaneously by energization of the appropriate vertical armatures 31, without returning the selecting bar to its neutral position. Further, it is apparent that if all five of the selecting bars 36 are rotated into one of their crosspoint closing positions, energization of each of the vertical armatures 31 will cause the closing of five of the crosspoints in its associated vertical unit assembly 12 simultaneously. Thus, up to fifty of the crosspoints 13 of the apparatus can be closed (or released) simultaneously, and all of the crosspoints can be closed (or released) in two stages, where desired.

While one embodiment of the invention has been disclosed, many modifications will be apparent and it is intended that the invention be interpreted as including all modifications which fall within the true spirit and scope of the invention.

What is claimed is:

1. Crossbar type switching apparatus, which comprises:

first and second adjacent sets of contacts;

contact selecting means movable selectively into either of two operative conditions each associated with a respective one of said sets of contacts;

releasable means cooperable with said contact selecting means when said contact selecting means is in either of its two operative conditions, for operating the one of said sets of contacts which is associated with that condition; and

separate mechanical locking means for each of said sets of contacts, for maintaining said set of contacts op erative so that said contact selecting means and said releasable means can be utilized to operate the other of said sets of contacts, each of said locking means being mounted at least in part on said contact selecting means for movement therewith into a respective one of its operative conditions.

2. Crossbar type switching apparatus, as recited in claim 1, in which the part of each of said mechanical locking means which is mounted on said contact selecting means is an elongated resilient finger.

3. Crossbar type switching apparatus, as recited in 4. Crossbar. type switching apparatus, which comprises:

first and second adjacent contact means;

movable operating members for moving respective ones of said contact means to operated positions;

contact selecting means movable selectively into either of two operative conditions each associated with a respective one of said operating members;

resilient fingers movable with said contact selecting means into engagement with tang portions of respective ones of said operating members as said contact selecting means moves into respective ones of its operative conditions;

fixed means adjacent said operating members; and

releasable means cooperable with said contact selecting means when said contact selecting means is in either of its operative conditions, for moving said operating member which is associated with that condition so that said operating member moves its respective contact means to its operated position and so that the tang portion of said operating member is moved into spaced relationship with respect to said fixed means whereby said resilient finger which is engaged with the tang portion moves into the space between the tang portion and said fixed means, said resilient finger subsequently being trapped between the tang portion and said fixed means upon the release of said releasable means so as to maintain said contact means operated whereby said contact selecting means and said releasable means can be utilized to move the other of said contact means to its operated position.

5. Crossbar type switching apparatus, which comprises:

first and second adjacent pairs of contact springs, said contact springs being insulated from one another and one contact spring of each pair being an input terminal and the other contact spring of each pair being an output terminal;

a terminal member for electrically interconnecting the input terminal contact spring and the output terminal contact spring of each pair of contact springs;

an operating card of insulating material engaged with each pair of contact springs and movable to move said contact springs into electrical contact with their interconnecting terminal member;

a movably mounted selecting bar;

a selecting finger mounted on said selecting bar;

first and second resilient fingers, one for each of said operating cards, mounted on said selecting bar;

fixed means adjacent said operating cards;

magnet means for moving said selecting bar selectively from a neutral position into either of two operative positions, to position said selecting finger adjacent one of said operating cards and to position a respective one of said resilient fingers in engagement with a tang portion of said operating card adjacent said fixed means; 7

a movable member extending adjacent said operating cards;

a magnet for moving said movable member after said selecting bar has been moved into either of its operative positions so that said movable member moves said selecting finger to move said operating card which said selecting finger is adjacent, whereby said operating card moves its respective pair of contact 10 springs into electrical contact with their interconnecting terminal member, and so that the tang portion on said operating card moves into spaced relationship with respect to said fixed means whereby said resilient finger which is engaged with the tang portion moves into the space between the tang portion and said fixed means; means for moving said movable member in a reverse direction upon de-energization of said magnet to release said selecting finger, with said operating card being moved in a reverse direction by said contact springs to trap said resilient finger between the tang portion'on said operating card and said fixed means so that said pair of contact springs is maintained in electrical contact with their interconnecting terminal member and said selecting finger and said movable member can be utilized to move the other of said pairs of contact springs into electrical contact with their interconnecting terminal member; and

restoring means for returning said selecting bar to its neutral position upon de-energization of said magnet means.

6. Crossbar type switching apparatus, which comprises:

a plurality of sets of contacts arranged in first and second intersecting rows;

separate contact selecting means for each pair of the first rows of said sets of contacts, each of said contact selecting means being selectively movable into either of two operative positions each associated with a respective one of the rows of its associated pair of first rows;

separate releasable means for each of the second rows of said sets of contacts, each of said releasable means being cooperable with each of said contact selecting means when said contact selecting means is in either of its two operative positions, for operating the one of said sets of contacts which is associated with said releasable means and with that position of said contact selecting means; and separate mechanical locking means for each of said sets of contacts, for maintaining said set of contacts operative so that said contact selecting means and said releasable means which are associated with said set of contacts can be utilized to operate any one of the other of their associated sets of contacts, each of said mechanical locking mechanical means being mounted at least in part on a respective one of said contact selecting means for movement therewith into a respective one of its operative positions.

7. Crossbar type switching apparatus, as recited in claim 6, in which the part of each of said locking means which is mounted on its respective one of said contact selecting means is an elongated resilient finger.

8. Crossbar type switching apparatus, as recited in claim 6, in which each of said sets of contacts includes an input contact, an output contact and a terminal member for electrically interconnect-ing said contacts, said vcontacts being movable into electrical contact with said terminal member by said releasable means which is associated with said set of contacts, in cooperation with said contact selecting means which is associated with said set of contacts.

9. Crossbar type switching apparatus, which comprises:

a set of contacts; a member adjacent said set of contacts and movable between inoperative and operative positions; an elongated first resilient finger mounted on said member for movement therewith between its inoperative and operative positions; releasable means cooperable with said elongated resilient finger when said member is in its operative position for operating said set of contacts; and mechanical locking means for maintaining said set of contacts operated when said releasable means is remeans and a tang portion on said operating card adleased and said member returns to its inoperative position, said locking means including an elongated second resilient finger mounted on said member. 10. Crossbar type switching apparatus, as recited in jacent an opposite end thereof, between which said second elongated resilient finger is trapped to maintain said set of contacts operated when said releasable means is released and said first-mentioned memclaim 9, her is returned to its inoperative position.

in which said releasable means includes a movable operating card of insulating material and a second mov- References Cited able member, said elongated first resilient finger being movable into a position between said second 10 UNITED STATES PATENTS member and an operating face on said operating 1,953,503 4/ 9 Reyn lds 335-112 card adjacent a first end thereof when said firstmen- 2,082,911 6/ 9 7 schneo'kloth 335112 tioned member is moved into its operative position, 2,301,472 12/1942 C flE h 335-1l2 and said second member subsequently being movable to move said first resilient finger and said operat- 15 BERNARD A. GILHEANY, Primary Examiner.

ing card to operate said set of contacts; and H BROOME Assistant Examiner in which said mechanical locking means includes fixed UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3,369,203 February 13, 1968 William J. Rea

It is hereby certified that error appears in the above numbered patent requiring correction and that the said Letters Patent should read as corrected below.

Column 10, line 47, strike out "mechanical", second occurrence.

Signed and sealed this 20th day of May 1969.

(SEAL) Attest:

Edward M. Fletcher, Jr.

Attesting Officer 

1. CROSSBAR TYPE SWITCHING APPARATUS, WHICH COMPRISES: FIRST AND SECOND ADJACENT SETS OF CONTACTS; CONTACT SELECTING MEANS MOVABLE SELECTIVELY INTO EITHER OF TWO OPERATIVE CONDITIONS EACH ASSOCIATED WITH A RESPECTIVE ONE OF SAID SETS OF CONTACTS; RELEASABLE MEANS COOPERABLE WITH SAID CONTACT SELECTING MEANS WHEN SAID CONTACT SELECTING MEANS IS IN EITHER OF ITS TWO OPERATIVE CONDITIONS, FOR OPERATING THE ONE OF SAID SETS OF CONTACT WHICH IS ASSOCIATED WITH THAT CONDITION; AND SEPARATE MECHANICAL LOCKING MEANS FOR EACH OF SAID SETS 